The Color Red
True to the Matched trilogy's dedication to three specific colors, Reached heavily features the color red in much of its imagery and plot devices. Red is described at many points in the story as the color of rebirth and new beginnings, and this theme resonates throughout in a book filled power transfers, changing fates, and tragic deaths. The presence of red begins with the book's very first paragraph, when Xander describes the sunrise turning the world red. It continues with a heavy focus on the role of the red tablet and Cassia's lack of immunity to it (though she is ultimately able to remember things despite its effects). Red is the color of the silk dress Cassia wears under her plainclothes in the Society, the mark that signals immunity from the mutation, the cures for the Plague, and the "red garden day" to which her grandfather's microcard alludes. Even Reached's book cover sports a girl in a bright red dress alongside red and white text.
The Color Blue
Though it plays a larger role in Reached's prequel, Crossed, the color blue is nevertheless important to this story, primarily in relation to its counterparts, green and red. These colors are often seen together in the Matched trilogy, for example the green, blue, and red tablets whose effects Cassia must fight against. Reached even ends with a nod to the color trifecta when Cassia says, "The river looks alternately blue and green as it reflects grass and sky, and I catch a glimpse of something red swimming in it."
The Color Green
Like red and blue, green plays an important recurring role in Matched trilogy. It was primarily focused on in the series' first installment, but Cassia's favorite color remains green, and green features heavily in many of her memories with Ky, from the green square of silk that she gave him to the lush vegetation of the Hill where they built their love. Green often represents nature and growth through the series. In Reached, it's referenced perhaps the least of the three colors, as there is a heavy focus on death and lack of growth through much of the story, though ultimately the green imagery does return as hope broadens.
Pilots
There is a heavy focus on the Pilot not only as a character but as a concept in Reached. The leader of the Rising is referred to only as the Pilot in the story, giving "pilot" a powerful association with leadership and hope. Yet throughout the book, there is much discussion over what it means to be a Pilot, who is and isn't one, and the idea that maybe what people really strive for is something or someone to believe in, which more often than not they can provide themselves. This ultimately ties into the story's moral that, rather than seeking a leader outside of us, we might look to ourselves.
Rebellion
The entire premise of Reached, and indeed, of the whole Matched trilogy, involves rebelling against an oppressive society that restricts people's basic freedoms. In the first book, this came in the form of Cassia's love for Ky despite being Matched to Xander, an explicit defiance of Society law. In Crossed, Cassia escapes into the Carving in an explicit act of rebellion against the Society. Finally, in Reached, the entire plot focuses around a full-scale rebellion on the part of the Rising in an attempt to overthrow the Society and create a free world for its citizens. Whether in small doses or total takeovers, rebellion plays a crucial role in Reached.
New Beginnings
As mentioned above, the red theme in Reached is inherently tied to the concept of new beginnings. There are many things that feel like new beginnings in the book: the Rising taking over the Society, the cure being administered to the sick, the second round of cures being administered to those with the mutation and, of course, the vote to decide on a new leader and society at the book's end. As the final installment in the series, Reached had the unique job of creating the conditions for change, for an ending that functions as the start of something new, and in this way, "new beginnings" is a theme of paramount significance.
Choice
Perhaps most sought after by the Rising members and citizens who are fed up with Society rule is the freedom to choose things for themselves. This theme has been salient since the series' first installment, when Cassia's rebellious nature was sparked by her choice to love Ky despite being Matched by the Society to Xander. Throughout Reached, Cassia learns of others' choices and the reasons behind them, including her father's controversial decision not to join the Rising when his father wanted him to. The reason that the ensuing argument ended up being Cassia's grandfather's favorite memory of her father is that it demonstrated to her grandfather that her father was capable of making and standing by his own choices, even when the former disagreed with them. Even Cassia's revelation that sometimes people choose wrongly when given total freedom of choice does not deter her from believing that such freedom is ultimately best; humans may make imperfect choices, but the freedom to have the option is the most important thing.
